Artificial foot.



I No. 734,926. PATENTED JULY 28, 1903.

W. I. MUMBERG.

ARTIFICIAL FOOT.

APPLICATION FILED APR. 30, 1903.

N0 MODEL.

Ice. 734,926.

UNITED STATES rammed July as, 1903.

PATENT OFFICE.

WILLIAM F. MUM-BERG, or CHICAGO, ILLINOIS;

ARTIFICIAL FOOT;

SPECIFICATION forming part of Letters Patent No. 734,926, dated July 28,1903 Application filed April 30,1903. Serial No. 155,073. (No model.)

T all whom it may concern:

Be it known that 1, WILLIAM F. ll/IUMBERG, a citizen of the UnitedStates, residing at Ohicago, in the county of Cook and State ofIllinois, have invented certain new and useful Improvements inArtificial-Foot Construc:

tion; and I do hereby declare the following to,

vide an artificial member of the character specified which will possessa maximum degree of flexibility and power to yieldingly conform to thevarious movements of the limb to which it is secured consistent with aproper location or disposition of the foot at all times, thereforeinsuring that all blows and jars incident to the use of the member willbe reduced to a minimum and a natural carriage or action of the limb towhich the foot is secured shall be attained.

A further object of my invention is to insure a perfect union of thevarious parts composing the foot and at the same time provide fornatural relative movements of all of the component parts, as will behereinafter more specifically set forth, reference being had to. theaccompanying drawings, which are made a part of this application, and inwhich Figure 1 shows a longitudinal central section of myimprovedartificial foot. Fig. .Zis a sectional view of the foot, taken on line 22 of Fig. 1. Fig. 3 is a sectional view on line 3 3 of Fig. 1. Fig. atis a detail view of a mud or shield disposed around the ankle portion,and Fig. 5 a plan view of the bolt used in connecting the partstogether.

In order to conveniently designate all of the various details of myinvention and accessories deemed necessary to show a practicalapplication thereof to use, numerals will be employed, the same numeralreferring to a similar part throughout the several views.

In carrying out my invention I provide the member 1, designed toconstitute the central portion of the foot proper, which is preferablyformed of some rigid substance, as wood or the like, and this centralmember 1 is Wholly embedded in or surrounded by a suitable material, ascomposition of canvas and rubber, (indicated by the numeral 2 in Fig.1,) it being understood that the composition forming the member 2 shouldbe ofjproper resilient or yielding character.

I provide for the upper side of the member 2 a convex or raised portion,as indicated by the numeral 3, said raised portion 3 being designed tofit in a suitable concavity provided upon the under side of the rocker0r ankle section 4, which latter is preferably formed. of some hardsubstance, as hickory wood, hard rubber, or other suitable material, itbeing understood that the contour or outline of the rocker or member 4shall conform in symmetry to the ankle portion of the foot. The ankleportion or rocker-section 4 is also provided with a substantiallycentrally disposed aperture in which is located acushion of rubber orother resilient material, as indicated by the numeral 5, and throughsaid cushion 5 and the raised member 3 I extend the lower end of thebolt or connecting-rod 6, which also reaches down through a suitableaperture in the central core 1, upon the lower side of which the T-head7 of the bolt is disposed, as clearly shown in Fig. 1. I also providethe ankle-section proper, 8, which is preferably hollow and is so formedas to have the horizontal section or cross-bar 9 near its upper end,said cross-bar being provided with an aperture to receive the upper endof the bolt or connecting-rod 6, said bolt being also of suificientlength to extend through the resilient cushion 10, of rubber or theequivalent. The extreme upper end of the bolt is threaded and adapted toreceive the clamping-nut 11, a suitable Washer 12 being interposedbetween the nut and the cushion 10. By adjusting said nut up or down theaction of the foot may be regulated-that is, when the nut is tightenedor turned down upon the bolt the rocker 4 will be held more firmlyagainst the flexible member 2, thus limiting the rocking movement of therocker 4 and adapting the movement thereof for slow walking, and whenthe nut is turned up or loosened the rocker 4 is given freer movementand adapting the foot for long strides or fast walking. In thisconstruction the cushion 10, in conjunction with the bolt 6 and rocker4, will regnlatethe action of the ballof the foot and lower part of theheel, the same as if flexible cords or the like were used to connect theparts, as indicated by the dotted lines 13 and 14, and the cushion 5, inconjunction with the bolt and rocker, controls the action of the instepand upper portion of the heel in like manner, as shown by the dottedlines 15 and 16. Inasmuch as the members 1, 4, and 8 are thus separatelyformed, it follows that they will possess the requisite amount ofrelative movement and at the same time all'of said parts will bereliably able to perform their office, while the cushioning members 5and 10 will permit a free flexing of the toe of the foot sufficient toclosely counterfeit the movements of the natural foot.

In order to present a neat and attractive appearance for the parts tocover the point of union of the ankle member 8 through the mediation ofthe rocker-section 4 with the foot proper, I provide the mufi orshield-sec tion 18, (shown as an entirety in Fig. 4,) consisting of apiece of suitable sheet metal extending entirely around theankle-section and overlapping each other upon the rear side, where thefree ends may be secured in any preferred way, as by riveting, brazing,or by passing screws through the apertures 19 and 20, as will be clearlyunderstood. This shield also serves to keep the foot portion fromturning and getting out of alinement with the ankle portion.

Itwill thus be seen that I have provided the component cooperating partsof an artificial foot, which will possess the requisite degree ofmobility for imitating the movements of the natural foot to the fullestpossible extent, and while I have described the preferred combinationand construction of parts I wish to comprehend such substantialequivalents and substitutes as may be considered as falling fairlywithin the scope and purview of my invention.

Believing that the construction and manner of assembling thevariousparts of my improved artificial foot have thus been made clearlyapparent, further description is deemed unnecessary.

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is

The herein-described artificial foot comprising the combination of acentral member proper 1 formed of relatively hard and rigid substanceand a covering for said part of yielding material formed of rubber andcanvas or the equivalent; an ankle portion of relatively hard substanceas hickory wood or the like; a raised member fitting a concave seat inthe under side of the ankle member; an ankle-section proper fitting uponthe ankle member and adapted to have a slight relative movementtherewith; a connecting-rod yieldingly uniting said parts; suitablecushionin g devices for said parts cooperatin g with said rod wherebythe foot proper will be held in a natural position though permitted toyieldingly conform to the movements thereof incident to the use, allcombined substant-ially as specified and for the'purpose setforth.

In testimony whereof I aflix my signature in presence of two witnesses.

WILLIAM F. MUMBERG.

\Vitnesses:

RICHARD A. PEAKE, JOHN DROHN.

